Team leader Namgyal Sherpa, who has climbed Everest seven times, says that ironically the unprecedented clean-up effort is made possible in part by global warming:

This is the first time we are cleaning at that height, the death zone. It is very difficult and dangerous. We will carry empty sacks and fill them with oxygen bottles, food wrappings, old tents and ropes. The garbage was buried under snow in the past. But now it has come out on the surface because of the melting of snow due to global warming.

The team plans to remove at least five unidentified bodies from a narrow trail between their camp just below the death zone and the 29,029ft (8,848m) summit. Another goal is removing 2,000 kilograms of garbage and the body of a Swiss climber who died two years ago. (The Swiss climber’s family has given permission for the remains to be cremated below the base camp.)

It is estimated that 120 bodies remain on Everest — which is nearly two-thirds of the 189 people who have lost their lives attempting to conquer Everest.